Ingot-heating furnace.



P. SCHMIDT & A. DESGRAZ.

INGOT HEATING FURNACE.

APPLICATION FILED JULY 16, 1907.

V 4 a m2 2 {Q Patented Nov. 10, 1908.

, AnoLrnn Because, a citizen of Switzerland,

our invention.

- out in the claim.

PAUL SCHMIDT AND ADOLPHE DESGRAZ, OF HANOVER, GERMANY.

incur-marine summon.

Specification of Letters Patent.

Patented Nov. 10, 1908.

Application and July 16, 1907 seri l na asa'iav.

To ullwhom it concern: l Be it known that we, PAUL Sonnm'r, a

subject of the Emperor of Germany, and

residing at Hanover, Germany, have invented certain new and usefulImprovements in bigot-Heating Furnaces, of which the following is aspecification.

This invention relates to furnaces for heating large ingots or blocks ofmetal and its object is to produce a furnace inwhich a number of largeingots may be heated thoroughly and without injury in suificientuantities to su ply the demands of the I rol g mill or ot er plant andin which cooling of the furnace and excessive consumption of fuel willbe avoided,

The invention consists in certain novel features of the furnaceillustrated in the accomanying drawings as will be hereinafter firstfully described and then particularly pointed v the drawings, Figure 1is a longitudinal sect1on,Fig. 2 a transverse section, and Fig. 3 ahorizontal section of a furnace embodymg The hearth roper of the furnaceis divided into any suitable number of chambers, a, b, c, d, e, thewallsv between which are provided close to the bottom and just above thehearth with apertures 9 through which the waste gases can pass from onechamber to. another. In the bottom of the hearth there are arranged anumber of stone ridges h which support the ingots and thus enable thewastegases to circulate beneath them. Instead of these ridges, severalloose stones may be placed upon the hearth. The front of each chamber isprovided with a door 71, and each chamber is provided with a separateadjustable gas supply. The gas passes from the gas supply pipe Kc by anyof the separateregw atin va ves Z, the ascending assages m, theistributing channels m w 'ch are ar-, ranged upon the furnace crown, andfinally throu h the various inlet nozzles 97. in. the arches crown ofthe furnace into theseparate chambers. The waste gases escapeat' bothsides of the furnace and pass through the fines o and 0 into theregenerators p andv p. The gases escaping on each side 0 the furnace'are consequently provided with a seriarate regenerator having a separateout at passage g or g' furnisheri with arelgulating valve '1 or 1*. Eachregenerator is a so separately supplied with air which enters N the I,but small.

passages s and 8 arranged at the two front ends of the furnace in ahighly heated condi tion and passes thence into the collecting chamber"6 arranged on the rear wall, where it is still further heated. Fromthis chamber theair is suppliedseparately and in adjustable quantitiesto the different chambers passing b means of the apertures w, which areprovi ed for each chamber and which can be regulated by means of theslides a, into the intermediate spaces, a between the double arches andfrom thence through larger mixing nozzles n, which are-arranged beneaththe nozzles a, into the furnace, being meanwhile intimately m'ixed withthe gas.

The method of operating the furnace is as follows: In the case inWhichthe furnace has been just constructed or'has been entirely out ofWork, some of the chambers, for instance, a, b and c, are filled withingots some hours before the beginning of the shift, the

heaviest ingot being referably put intothe central chamber 0 am thelightest ingots into the outer chamber a. The slide 1 is then opened topermit of the escape of the Waste gases-through the flue 0 the slide 1'meanwhile remaming closed. By means of the regulating device the supplyof gas is so regulated that the maximum amount of gas and acorresponding amount of air passes into the central chamber. 0, whilethe chamber 1) is supplied with a correspondingly smaller amount of gasand the chamber a with no gas at all, provided the ingots placed thereinare As the waste gases of all the three chambers pass away in the firstinstance through 0 they will be forced to pass throu h the aperturesarran ed in the partition Wa ls f from chamber to c amber, passingthereby to a large extent beneath the ingots and giving up to them alarge portion of'their heat which hitherto has been lost. The supply ofgas to the side chambers from above is con with the result that thewaste gases will now o'cks thorillQ - time the ingot in chamber 0 willlikewise be hot blocks. When the ingots in chamber a,

have been allworked up, this chamber is at once again filledandmorewaste gas is caused to pass through, 0 The same process is reeatedwhen all the blocks in chamber b have een used up and the chamber hasagain been filled with new ingots, the only difierencebein that nowagain there is supplied a suitable amount of air-and gas mixture. Bythis ready to be Withdrawn. After this chamber has also again beencharged, the Waste ases thereof are first caused to escapethroug 0 whilethe ingots in the chambers d and e, which in the meantime have becomehot, are Withdrawn. The furnace'will now be in regular working order andis alternately emptied chamber by chamber from one side or the other andagain charged. The newly inserted cold ingots cannotpossibly affect thealready heated ingots as the hot partition walls f act as insulators orbuffers and at the same time, by means of the heat stored in them,assist in the heating of the ingots. By heating each chamber separatelyto a greater or less extent and by varyin the direction of flow of thewaste gases from c amber to cham ber, the furnace may be operated invarious different ways, for instance, only one, or two, or threechambers may be used, without consuming a relatively larger amount ofcoal. The furnace is moreover suitable for ingots of all sizes, from thelargest down to the smallest.

The furnace satisfies therefore all the above-mentioned conditions inthe most satisfactory manner. It'perrnits of the gradual heating ofvtheheavy ingots, it insuresan absolutely uniform heating of the in ots 1throughout asthe ingots are surrounde on all sides, above as well asbeneath, by, the heating" gases, and finally it makes continuousworkingpossible. I The manner in which 7 the furnace 1s operated,-moreover,rreduces the wasteuofiron to the smallest amount as the ingotsare subjects to the greatest heat in the order in which they areWithdrawn and areconsequently not exposed to this heat longer than isabsolutely necesossible 5o sary, a factwhich explains without furtherremark the small coal consumption of the furnace.

Having now particularly described and as;

certained tthe nature of ourisaid invention and in what manner thesame1s to be per- An ingot-heating furnace having, a plurality ofheating-chambers, means for supply ing gas to the chambers, means forcausing the gas'to travel successively throughflqthe chambers, aregenerator, a passage leading from the end chamber to the regenerator,

and an outlet from the regenerator 'common.

to all the chambers.

In testimony whereof-We have hereunto f set our hands inpresence of twosubscribing Witnesses. I PAUL SCHMIDT ADOLPHE, DESGRAZ." I

Witnesses: PAUL R. THOMPSON, ROBERT V. BULON.

